1. Field of the Invention
The present invention is directed to a method for franking postal matter and for checking the franking as well as a system for the implementation of such a as well as a postage meter apparatus for franking postal matter.
2. Description of the Prior Art
Like many other concerns, postal services in many countries of the world are increasingly carrying out commerce electronically, referred to as electronic commerce (e-commerce). Conventionally, large concerns use postage meter machines for franking their postal matter. Such postage meter machines are licensed to registered persons and require a specific connection to the postal service in order to be able to reload postage fees for the franking. In such a closed franking system, mechanical franking machines are reloaded with physical jetons (tokens) or the electronic postage meter machines have connections to the postal service via a special line or via the telephone line in order to be able to download postage fees from a fee computer thereat. Such postage meter machines are only sold or leased to registered customers, and an inspection by the postal service is required at regular intervals.
Since smaller companies and offices also have adequate computer capacity and printers available and an Internet connection is available in a simple and economic way, franking systems are being increasingly employed with which postage fees can be downloaded from the postal service via open networks such as the Internet and that require no special hardware subject to a regular inspection requirement. In systems referred as open franking systems, a conventional PC can be used for downloading the postage fees, and a standard printer can be used for printing a fee stamp on an envelope or on a label.
The U.S. Postal Service has specific a system architecture for open and closed franking systems. Such a system is disclosed, for example, in U.S. Pat. No. 5,825,893. Each user has a physical, theft-proof security device on which all postage fees of the user provided for the franking are stored. This security device (PSD=Postal Security Device) can be arranged inside or outside the postage meter machine or the computer. The basic items arranged in a security device are a fee counter and a user-associated encryption module with which the fee stamp and a further, machine-readable date stamp, referred to as “indicia”, are generated. For franking a postal item, the security device generates such an indicium from the postage fee to be franked, and an identification code of the security device, the sender address, the current fee counter reading and, if necessary, further data with a signature code. This indicium is then encoded in a two-dimensional bar code and is printed to the postal matter, so that it can be scanned and inspected in a simple and dependable way by an evaluation device of the postal service. The internal postage fee counter of the postage meter machine is subsequently reduced (decremented) by the amount of postage that has been employed.
Since the users of open franking systems are not registered and the hardware that is employed is not subject to any regular inspections by the postal service, such franking systems must be protected more extensively against fraud than are closed franking systems. Open systems, however, also must be significantly cheaper in order to be able to become popular in the mass market.